Is it possible to create a custom segment that is made up of multiple locations? Example: Custom Segment #1: Location 1 Location 2 Location 3 Custom Segment #2: Location 4 Location 5

you mentioned earlier it's jsut for reporting purposes - you can create custom reporting groups in your financial reports if you want which might be easier than a whole new segment which might require scripting to associate like you have above

how do you go about creating custom reporting groups?